divideBy with positive integers
auto result = 10.divideBy(5); result.isRight.should.equal(true); result .when((int value) { value.should.equal(2); });
divideBy when the denominator is 0
auto result = 10.divideBy(0); result.isLeft.should.equal(true); result .when((string value) { value.should.equal("Division by zero!"); });
divideBy when the denominator is NaN
double nan; auto result = double(10).divideBy(nan); result.isLeft.should.equal(true); result .when((string value) { value.should.equal("Denominator is NaN."); });
divideBy when the Numerator is NaN
double nan; auto result = double.nan.divideBy(3); result.isLeft.should.equal(true); result .when((string value) { value.should.equal("Numerator is NaN."); });